RDS-2

The RDS-2 (Russian: РДС-2) was the second atomic bomb developed by the Soviet Union as an improved version of the RDS-1. It included new explosive lenses along with a new core design to decrease the probability of pre-detonation or 'fizzle'. The RDS-2 weighed approximately 3200 kg and had a diameter of 1.25 m. The RDS-2 was tested on September 24, 1951 and produced a 38.3 kiloton yield. It was detonated from the top of a tower thirty meters high. The detonation was controlled by a bomber flying over the testing site instead of the detonation being controlled by a ground control center.